This invention relates to a hydraulic system for controlling the telescoping boom sections of a crane and more particularly concerns an improved apparatus for preventing the hoses of the hydraulic system from becoming fouled and tangled.
One of the problems encountered in cranes having telescoping boom sections has been the difficulty involved in retracting and paying-out the hose of the hydraulic system during the telescoping of the boom sections. Heretofore various types of reel and travelling pulley arrangements have been employed to prevent the fouling and kinking of the hydraulic hoses with varying degrees of success. The U.S. Pat. No. 3,305,220 to Nevulis discloses a travelling carriage; the U.S. Pat. No. 3,056,610 to Garrett discloses a spring-loaded pulley arrangement; and the U.S. Pat. No. 4,125,974 to Kay et al discloses a pulley disposed between adjacent walls of adjacent telescoping boom sections and a spring-loaded cable system for maintaining a pulling force on the pulley to keep the hose taut and in an untangled condition during relative movement of the boom sections. It is evident that in any mechanism used in heavy outdoor machinery, such as cranes, it is an advantage to have as few parts that require adjustment, servicing and replacement as possible. Springs that change their spring rate over a period of time or rust-up due to exposure to the elements could result in an unacceptable amount of down-time for a crane.
It is an object of the present invention to provide a hose take-up system which has a minimum of parts and is effective to keep the hose under tension without the use of springs.